H5 animation audio doesn't play on mobile browser

[You24637027rsiv]

I made an H5 animation with audio and sound effects using Animate CC 2019. The audio works well on the laptop PC, but it doesn't work on mobile. 
This H5 animation I designed is mainly for mobile browsers. Can anyone help me out?

Thank you so much!

[You24637027rsiv]

Here is the url of the project:

https://animatetest-5gym6bfh0b915155-1300228947.ap-shanghai.app.tcloudbase.com/infobox1.html 

When you tap the blinking spot, the sound should play. It doesn't work on mobile, however.

Thanks!